Submission #1595562

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Source Code Expand

#include <bits/stdc++.h>

using namespace std;

int n, k;
string s;
int c[26];

bool check(int pos, int k_) {
  int c2[26];
  memmove(c2, c, sizeof(c2));

  for (int i = pos; i < n; i++) {
    if (c2[s[i] - 'a'] > 0) c2[s[i] - 'a']--;
    else k_--;
  }
  return k_ >= 0;
}

int main(void) {
  cin >> n >> k >> s;

  for (int i = 0; i < n; i++) {
    c[s[i] - 'a']++;
  }

  string ans = "";
  for (int i = 0; i < n; i++) {
    for (char ch = 'a'; ch <= 'z'; ch++) {
      int j = ch - 'a';
      if (c[j] <= 0) continue;
      c[j]--;
      if (s[i] != ch) k--;
      if (check(i + 1, k)) {
        ans += ch;
        break;
      }
      if (s[i] != ch) k++;
      c[j]++;
    }
  }

  cout << ans << endl;

  return 0;
}

Submission Info

Judge Result